arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2003.03187stat.MEstat.CO
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存在陷门变量的小数据因果效应估计

Estimation of causal effects with small data in the presence of trapdoor variables

Jouni Helske, Santtu Tikka, Juha Karvanen

摘要:

我们考虑的问题,估计因果影响的干预措施的观察数据时,众所周知的后门和前门的调整是不适用的。我们发现,当一个可识别的因果效应受到一个隐式的功能约束,这是不能推断的条件独立关系,估计的因果效应可以表现出偏差在小样本。这种偏差与我们称之为陷门变量的变量有关。我们使用模拟数据来研究不同的策略来解释陷门变量,并建议如何最大限度地减少相关的陷门偏差。陷门变量在因果效应估计中的重要性用生命历程1971-2002研究的真实数据来说明。使用这个数据集,我们估计在芬兰的背景下,教育对收入的因果关系。贝叶斯模型允许我们考虑参数的不确定性,并将估计的因果效应表示为后验分布。

英文摘要:

We consider the problem of estimating causal effects of interventions from observational data when well-known back-door and front-door adjustments are not applicable. We show that when an identifiable causal effect is subject to an implicit functional constraint that is not deducible from conditional independence relations, the estimator of the causal effect can exhibit bias in small samples. This bias is related to variables that we call trapdoor variables. We use simulated data to study different strategies to account for trapdoor variables and suggest how the related trapdoor bias might be minimized. The importance of trapdoor variables in causal effect estimation is illustrated with real data from the Life Course 1971-2002 study. Using this dataset, we estimate the causal effect of education on income in the Finnish context. Bayesian modelling allows us to take the parameter uncertainty into account and to present the estimated causal effects as posterior distributions.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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